Removable



March 1, 1932. L. D. HARNETT REMOVABLE FILTER UNIT HEATER Filed Aug. 29, 1929 3 Sheets-Sheet A o 1.1 v

1 VENTOR BY N WWW

A TTORNEY March I,- 1932.

L. D. HARNETT REMOVABLE FILTER UNIT HEATER Filed Aug. 29, 1929 3 Sheets-Sheet 2 u UDUUUU immmmmm immmmmm UDUUUU M55555 -immmmum mmmmmm ATTORNEY March 1932- D. HARNEfT REMOVABLE FILTER UNIT HEATER 3 Sheets-Sheetv Filed Aug. ?9, 1929 repairs I unlocking the. cabinets Patented Mar. 1, 1932 UNITED STATES PATENT OFFICE LEWIS D. HARNETT,'OF COLUMBUS, OHIO, ASSIGNOR, BY MESNE ASSIGNMENTS, TO BUCKEYE'BLOWEB COMPANY, A. CORPORATION OF DELAWARE REMOVABLE FILTER UN TT HEATER Application filed August 29, 1929. Serial No. 889,163.

My invention relates to heating and ventilating apparatus and in particular to unit heaters and ventilators.

It is the object of my invention to provide a detachable and removable filtering medium which may be removed from the unit heater.

and ventilator for cleaning, replacement and without the necessity of unlocking the heater. It will be understood that the unit heater and ventilator has its mechanism enclosed in a casing which is securely locked to prevent tampering with the adjustments. It has been found that very serious consequences in upsetting the delicate adjustments of such unit have resulted from the necessity if having them opened by persons who must remove and clean the filters. The temptation to tamper with the mechanism has resulted in disturbing the apparatus which such persons are not authorized to deal with.

It is also a tedious processof locking and in order to get at the filters and in large buildings where there are many such units it is an item of cost of major importance.

It is the object of my present invention to be able to remove and install the filters without opening the cabinets.

mg 2 into the air inlet damper compartment 3 controlled by the damper 4. Fresh air enters through the opening 2 from the outside of the building or air from the inside of the room may enter the chamber 3 through the grille opening 5. The air then passes upwardly through the filtering medium ofthe steel wool'6 carried in the cage 7. This cage the line 1-1 or frame has retaining grille members 8 as well as the bottom. The entire unitary structure slides into position on the bottom frame members 9 and 10 and beneath the upper frame members 11 and 12. The front of the filter frames carries a detachable cover 13 having a handle 14. The cover engages the main casing 1 alone with turned over edges 15 so that any buckling of the cover will not cause leakage. The cover is detachably mounted on the frame by the tonguelfi entering the loop 17. This filter may be locked into position if desired, but usually that is not necessary as the case itself is locked by the lock 18. The air is drawn upwardly through the filter by the blower 19 and discharged over the radiator 20 or through the bypass passageway 21 according to the position of the dampers 22 and 23 controlled by the link system 24. The air then passes outwardly through the grilled exit 25. Thus the air passes in a straight line path from either the outside or the inside of the roof first through the filtering medium and thence into the blower and over the radiator, or into the bypass. This preliminary cleaning removes the foreign material so that there will be no accumulation on the blades of the fan, the motor or upon the radiator to reduce the radiation. It also removes the foreign material from the air.

It will be understood that these steel wool filters are cleaned by immersing in cleaning liquid or spraying or subjecting to other treatment so that it is highly desirable to remove the cover 13 which forms a part of the decorative casing in order that it shall not become injured by this cleaning treatment.

It will be understood that I desire to com prehend within my invention and within the scope of my claim such modifications as may be fairly comprehended within such claim and invention due to necessary modifications to adapt my invention to varying conditions of use and to varying purposes.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent, is:

In a unit heater and ventilator having a bottom inlet opening and a top exit opening, air inlet compartment, a filtering compartment, a blower and a radiator in the order named from bottom to top, a removable filter in said filtering compartment ada ted to be removed without opening the unit eater and ventilator to expose the remainder of the mechanism and'an enclosure on said filter casing in engagement with the unit and ventilator casing to form a sealed enclosure when a the filter is in place.

In testimony whereof I aflix my si nature.

' NiETT. e

LEWIS D. HAR 

